IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.2.138.0/24

network10.2.138.0/24

broadcast10.2.138.255

first host10.2.138.1

last host10.2.138.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.138.0/24

address00001010.00000010.10001010.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10001010.00000000

broadcast00001010.00000010.10001010.11111111

green = network part, grey = host part

hex0x0a028a00

decimal167938560

reverse dns0.138.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:8a00

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.138.0/31	10.2.138.0 – 10.2.138.1	10.2.138.1
2	10.2.138.2/31	10.2.138.2 – 10.2.138.3	10.2.138.3
3	10.2.138.4/31	10.2.138.4 – 10.2.138.5	10.2.138.5
4	10.2.138.6/31	10.2.138.6 – 10.2.138.7	10.2.138.7
5	10.2.138.8/31	10.2.138.8 – 10.2.138.9	10.2.138.9
6	10.2.138.10/31	10.2.138.10 – 10.2.138.11	10.2.138.11
7	10.2.138.12/31	10.2.138.12 – 10.2.138.13	10.2.138.13
8	10.2.138.14/31	10.2.138.14 – 10.2.138.15	10.2.138.15
9	10.2.138.16/31	10.2.138.16 – 10.2.138.17	10.2.138.17
10	10.2.138.18/31	10.2.138.18 – 10.2.138.19	10.2.138.19
11	10.2.138.20/31	10.2.138.20 – 10.2.138.21	10.2.138.21
12	10.2.138.22/31	10.2.138.22 – 10.2.138.23	10.2.138.23
13	10.2.138.24/31	10.2.138.24 – 10.2.138.25	10.2.138.25
14	10.2.138.26/31	10.2.138.26 – 10.2.138.27	10.2.138.27
15	10.2.138.28/31	10.2.138.28 – 10.2.138.29	10.2.138.29
16	10.2.138.30/31	10.2.138.30 – 10.2.138.31	10.2.138.31
17	10.2.138.32/31	10.2.138.32 – 10.2.138.33	10.2.138.33
18	10.2.138.34/31	10.2.138.34 – 10.2.138.35	10.2.138.35
19	10.2.138.36/31	10.2.138.36 – 10.2.138.37	10.2.138.37
20	10.2.138.38/31	10.2.138.38 – 10.2.138.39	10.2.138.39
21	10.2.138.40/31	10.2.138.40 – 10.2.138.41	10.2.138.41
22	10.2.138.42/31	10.2.138.42 – 10.2.138.43	10.2.138.43
23	10.2.138.44/31	10.2.138.44 – 10.2.138.45	10.2.138.45
24	10.2.138.46/31	10.2.138.46 – 10.2.138.47	10.2.138.47
25	10.2.138.48/31	10.2.138.48 – 10.2.138.49	10.2.138.49
26	10.2.138.50/31	10.2.138.50 – 10.2.138.51	10.2.138.51
27	10.2.138.52/31	10.2.138.52 – 10.2.138.53	10.2.138.53
28	10.2.138.54/31	10.2.138.54 – 10.2.138.55	10.2.138.55
29	10.2.138.56/31	10.2.138.56 – 10.2.138.57	10.2.138.57
30	10.2.138.58/31	10.2.138.58 – 10.2.138.59	10.2.138.59
31	10.2.138.60/31	10.2.138.60 – 10.2.138.61	10.2.138.61
32	10.2.138.62/31	10.2.138.62 – 10.2.138.63	10.2.138.63
33	10.2.138.64/31	10.2.138.64 – 10.2.138.65	10.2.138.65
34	10.2.138.66/31	10.2.138.66 – 10.2.138.67	10.2.138.67
35	10.2.138.68/31	10.2.138.68 – 10.2.138.69	10.2.138.69
36	10.2.138.70/31	10.2.138.70 – 10.2.138.71	10.2.138.71
37	10.2.138.72/31	10.2.138.72 – 10.2.138.73	10.2.138.73
38	10.2.138.74/31	10.2.138.74 – 10.2.138.75	10.2.138.75
39	10.2.138.76/31	10.2.138.76 – 10.2.138.77	10.2.138.77
40	10.2.138.78/31	10.2.138.78 – 10.2.138.79	10.2.138.79
41	10.2.138.80/31	10.2.138.80 – 10.2.138.81	10.2.138.81
42	10.2.138.82/31	10.2.138.82 – 10.2.138.83	10.2.138.83
43	10.2.138.84/31	10.2.138.84 – 10.2.138.85	10.2.138.85
44	10.2.138.86/31	10.2.138.86 – 10.2.138.87	10.2.138.87
45	10.2.138.88/31	10.2.138.88 – 10.2.138.89	10.2.138.89
46	10.2.138.90/31	10.2.138.90 – 10.2.138.91	10.2.138.91
47	10.2.138.92/31	10.2.138.92 – 10.2.138.93	10.2.138.93
48	10.2.138.94/31	10.2.138.94 – 10.2.138.95	10.2.138.95
49	10.2.138.96/31	10.2.138.96 – 10.2.138.97	10.2.138.97
50	10.2.138.98/31	10.2.138.98 – 10.2.138.99	10.2.138.99
51	10.2.138.100/31	10.2.138.100 – 10.2.138.101	10.2.138.101
52	10.2.138.102/31	10.2.138.102 – 10.2.138.103	10.2.138.103
53	10.2.138.104/31	10.2.138.104 – 10.2.138.105	10.2.138.105
54	10.2.138.106/31	10.2.138.106 – 10.2.138.107	10.2.138.107
55	10.2.138.108/31	10.2.138.108 – 10.2.138.109	10.2.138.109
56	10.2.138.110/31	10.2.138.110 – 10.2.138.111	10.2.138.111
57	10.2.138.112/31	10.2.138.112 – 10.2.138.113	10.2.138.113
58	10.2.138.114/31	10.2.138.114 – 10.2.138.115	10.2.138.115
59	10.2.138.116/31	10.2.138.116 – 10.2.138.117	10.2.138.117
60	10.2.138.118/31	10.2.138.118 – 10.2.138.119	10.2.138.119
61	10.2.138.120/31	10.2.138.120 – 10.2.138.121	10.2.138.121
62	10.2.138.122/31	10.2.138.122 – 10.2.138.123	10.2.138.123
63	10.2.138.124/31	10.2.138.124 – 10.2.138.125	10.2.138.125
64	10.2.138.126/31	10.2.138.126 – 10.2.138.127	10.2.138.127
65	10.2.138.128/31	10.2.138.128 – 10.2.138.129	10.2.138.129
66	10.2.138.130/31	10.2.138.130 – 10.2.138.131	10.2.138.131
67	10.2.138.132/31	10.2.138.132 – 10.2.138.133	10.2.138.133
68	10.2.138.134/31	10.2.138.134 – 10.2.138.135	10.2.138.135
69	10.2.138.136/31	10.2.138.136 – 10.2.138.137	10.2.138.137
70	10.2.138.138/31	10.2.138.138 – 10.2.138.139	10.2.138.139
71	10.2.138.140/31	10.2.138.140 – 10.2.138.141	10.2.138.141
72	10.2.138.142/31	10.2.138.142 – 10.2.138.143	10.2.138.143
73	10.2.138.144/31	10.2.138.144 – 10.2.138.145	10.2.138.145
74	10.2.138.146/31	10.2.138.146 – 10.2.138.147	10.2.138.147
75	10.2.138.148/31	10.2.138.148 – 10.2.138.149	10.2.138.149
76	10.2.138.150/31	10.2.138.150 – 10.2.138.151	10.2.138.151
77	10.2.138.152/31	10.2.138.152 – 10.2.138.153	10.2.138.153
78	10.2.138.154/31	10.2.138.154 – 10.2.138.155	10.2.138.155
79	10.2.138.156/31	10.2.138.156 – 10.2.138.157	10.2.138.157
80	10.2.138.158/31	10.2.138.158 – 10.2.138.159	10.2.138.159
81	10.2.138.160/31	10.2.138.160 – 10.2.138.161	10.2.138.161
82	10.2.138.162/31	10.2.138.162 – 10.2.138.163	10.2.138.163
83	10.2.138.164/31	10.2.138.164 – 10.2.138.165	10.2.138.165
84	10.2.138.166/31	10.2.138.166 – 10.2.138.167	10.2.138.167
85	10.2.138.168/31	10.2.138.168 – 10.2.138.169	10.2.138.169
86	10.2.138.170/31	10.2.138.170 – 10.2.138.171	10.2.138.171
87	10.2.138.172/31	10.2.138.172 – 10.2.138.173	10.2.138.173
88	10.2.138.174/31	10.2.138.174 – 10.2.138.175	10.2.138.175
89	10.2.138.176/31	10.2.138.176 – 10.2.138.177	10.2.138.177
90	10.2.138.178/31	10.2.138.178 – 10.2.138.179	10.2.138.179
91	10.2.138.180/31	10.2.138.180 – 10.2.138.181	10.2.138.181
92	10.2.138.182/31	10.2.138.182 – 10.2.138.183	10.2.138.183
93	10.2.138.184/31	10.2.138.184 – 10.2.138.185	10.2.138.185
94	10.2.138.186/31	10.2.138.186 – 10.2.138.187	10.2.138.187
95	10.2.138.188/31	10.2.138.188 – 10.2.138.189	10.2.138.189
96	10.2.138.190/31	10.2.138.190 – 10.2.138.191	10.2.138.191
97	10.2.138.192/31	10.2.138.192 – 10.2.138.193	10.2.138.193
98	10.2.138.194/31	10.2.138.194 – 10.2.138.195	10.2.138.195
99	10.2.138.196/31	10.2.138.196 – 10.2.138.197	10.2.138.197
100	10.2.138.198/31	10.2.138.198 – 10.2.138.199	10.2.138.199
101	10.2.138.200/31	10.2.138.200 – 10.2.138.201	10.2.138.201
102	10.2.138.202/31	10.2.138.202 – 10.2.138.203	10.2.138.203
103	10.2.138.204/31	10.2.138.204 – 10.2.138.205	10.2.138.205
104	10.2.138.206/31	10.2.138.206 – 10.2.138.207	10.2.138.207
105	10.2.138.208/31	10.2.138.208 – 10.2.138.209	10.2.138.209
106	10.2.138.210/31	10.2.138.210 – 10.2.138.211	10.2.138.211
107	10.2.138.212/31	10.2.138.212 – 10.2.138.213	10.2.138.213
108	10.2.138.214/31	10.2.138.214 – 10.2.138.215	10.2.138.215
109	10.2.138.216/31	10.2.138.216 – 10.2.138.217	10.2.138.217
110	10.2.138.218/31	10.2.138.218 – 10.2.138.219	10.2.138.219
111	10.2.138.220/31	10.2.138.220 – 10.2.138.221	10.2.138.221
112	10.2.138.222/31	10.2.138.222 – 10.2.138.223	10.2.138.223
113	10.2.138.224/31	10.2.138.224 – 10.2.138.225	10.2.138.225
114	10.2.138.226/31	10.2.138.226 – 10.2.138.227	10.2.138.227
115	10.2.138.228/31	10.2.138.228 – 10.2.138.229	10.2.138.229
116	10.2.138.230/31	10.2.138.230 – 10.2.138.231	10.2.138.231
117	10.2.138.232/31	10.2.138.232 – 10.2.138.233	10.2.138.233
118	10.2.138.234/31	10.2.138.234 – 10.2.138.235	10.2.138.235
119	10.2.138.236/31	10.2.138.236 – 10.2.138.237	10.2.138.237
120	10.2.138.238/31	10.2.138.238 – 10.2.138.239	10.2.138.239
121	10.2.138.240/31	10.2.138.240 – 10.2.138.241	10.2.138.241
122	10.2.138.242/31	10.2.138.242 – 10.2.138.243	10.2.138.243
123	10.2.138.244/31	10.2.138.244 – 10.2.138.245	10.2.138.245
124	10.2.138.246/31	10.2.138.246 – 10.2.138.247	10.2.138.247
125	10.2.138.248/31	10.2.138.248 – 10.2.138.249	10.2.138.249
126	10.2.138.250/31	10.2.138.250 – 10.2.138.251	10.2.138.251
127	10.2.138.252/31	10.2.138.252 – 10.2.138.253	10.2.138.253
128	10.2.138.254/31	10.2.138.254 – 10.2.138.255	10.2.138.255

01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefix	subnet mask	addresses	hosts	in your /24
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	-
/22	255.255.252.0	1,024	1,022	-
/23	255.255.254.0	512	510	-
/24	255.255.255.0	256	254	1
/25	255.255.255.128	128	126	2 split →
/26	255.255.255.192	64	62	4 split →
/27	255.255.255.224	32	30	8 split →
/28	255.255.255.240	16	14	16 split →
/29	255.255.255.248	8	6	32 split →
/30	255.255.255.252	4	2	64 split →
/31	255.255.255.254	2	2	128 split →
/32	255.255.255.255	1	1	256 split →

02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →